The Ireland and Lions lock said afterwards: "There's no doubt as a team we were a bit rusty. That's something we had to play down during the week and we had to try and convince ourselves we could hit the ground running. We did at the start of the game, but we need to do that for 80 minutes. Hopefully with games we can."
Ronan O'Gara launches over one of his four second half penalties on the way to a 14-point haul. O'Gara was a doubtful starter before kick-off after tweaking his hamstring during the week, but coach Declan Kidney was pleased his first choice number 10 came through for him. Kidney said: "The weather in Munster during the week was very bad and we trained on some very heavy pitches. Ronan is a perfectionist and that could have affected him. We took him off at the end just to give young Jeremy Manning a taste of European rugby.
"Ronan was very brave in going in for that ball in the second half and got a bad gash on the knee. But the medics got him up and he was vital (to us) in the last few minutes."
Munster full back Shaun Payne launches a pass over the head of Perpignan's only scorer throughout the game - winger Mathieu Bourret, who scored a try, converted it and added a penalty, all in the first half.
Perpignan lock Nathan Hines competes for possession with Munster's David Wallace and Donncha O'Callaghan.
Munster prop Marcus Horan, reflecting on the game, was thankful that the province kept their discipline. "Our discipline held out," said the Shannon clubman, "and that was where the game was won. The penalties were a big thing. We seemed to get ours and put them over. Our discipline was superb - it's important against a team like Perpignan that you keep your head and stay focused because it can get frustrating out there.
"There were a lot of rucks spoiled and moves that broke down because of their indiscipline. The referee did well - he gave us the penalties. We'd prefer to finish them off over the try line, rather than having to take the kicks, but you've got to take it when you get it."
Munster's Peter Stringer closes his opposite number Nicolas Durand down as he attempts a clearance. Stringer's every readiness has seen him star for Ireland in recent seasons, hardly missing a game for Eddie O'Sullivan's side, and the same can be said in Europe.
The semi-final clash against Leinster will be the 5ft 7in pivot's 60th Heineken Cup appearance, and only one of his previous 59 caps have been as a replacement. Back from injury, he came off the bench to replace Anthon Pitout against Sale in Munster's pool stage opener last October.
A touchline scuffle towards the end of the first half saw Marcus Horan get involved with Perpignan captain Manny Edmonds. Horan, already focusing on the semi-final, admitted afterwards: "We're in a semi-final now and, having not been together for so long, we've got to be happy about it. The other side of it though is that we've a lot of work to (ahead of Leinster) and we know it."
Perpignan lock Rimas Alvarez Kairelis and Munster duo Jerry Flannery and Paul O'Connell almost end up in the crowd as tempers flare on the cusp of half time.
**All photos by Tom Honan and Morgan Treacy of Inpho Photography**